Magnetic Drain Plugs Hardly get a Mention. Why?

[ZeeOSix]

Originally Posted By: CurtisB
My concern with a filter magnet would actually be with the placement of the filter bypass valve. If a magnet has particles trapped against the filter housing, could a high pressure bypass scenario dislodge some of the trapped metals and enter the bypass valve (being if the filter has a dome end bypass).


"high pressure bypass scenario" ... humm. When an oil filter goes into bypass, there really isn't any "high pressure" involved. And the oil flow volume going through the filter really doesn't change in the amount since the oil pump is positive displacement ...it just changes flow paths.

Now if for some reason the magnet placed on the oil filter was in a flow "dead zone" (around the dome end), and all of a sudden the bypass valve opened it got some of the oil flow volume swept past it, then it might be possible some debris could be dislodged if the bypass flow was significant. But I don't think this situation really occurs because bypass valves usually just crack open and let a small portion of the total flow through the valve. To be safe, just don't put the magnets on the dome end of the filter, but rather on the sides of the can like a FilterMag does.

Originally Posted By: CurtisB
I myself would be concerned with the sudden entry of metallic wear particles, some of which would have been trapped in the filter media without the magnet present.


In a bypass event, there is still some oil flowing through the media, so what's trapped in the media, stays in the media. It doesn't magically jump off the media against the direction of the oil flow going through the media.

 

[paulo57509]

I think the intent for a magnetic drain plug is to catch particles as a visual indicator that something is going wrong and needs attention, unlike a filter magnet. If you see more particles on the plug this OCI than the last time sort of thing.

I seem to recall seeing a magnetic drain plug kit that was wired to a warning light in a normally open circuit. Once the particles bridged the "open" the light would turn on. Might have been in a aircraft accessory catalog

 

[CurtisB]

I definitely typed in some incorrect info there, I was under the impression that new Ford aluminum blocks had hardened cylinder walls VIA a process called Plasma Transferred Wire Arc. In which I would still be incorrect because that process still uses iron apparently. Some quick Google searches I found that Ford is still using iron cylinder sleeves in new aluminum block motors, I apologise for my ignorance on that part.

 

[CurtisB]

Originally Posted By: ZeeOSix
Originally Posted By: CurtisB
I myself would be concerned with the sudden entry of metallic wear particles, some of which would have been trapped in the filter media without the magnet present.


In a bypass event, there is still some oil flowing through the media, so what's trapped in the media, stays in the media. It doesn't magically jump off the media against the direction of the oil flow going through the media.


Nowhere in my post did I say that particles lodged in the filter media would become magically dislodged, I was pertaining to metallic particles that are trapped against the filter magnet and would probably otherwise be lodged in the filter media without the magnet present. There isn't any high pressure involved in an oil filter bypass opening? Is that not why there is a bypass valve with a pre-set spring tension in the first place? I would have thought an oil filter bypass was in place to deal with abnormal pressures that may present within the filter, much like a cold winter start, and it opens to assure the flow of lubricant rather than have a backlog against the media.

 

[ZeeOSix]

Originally Posted By: CurtisB
There isn't any high pressure involved in an oil filter bypass opening? Is that not why there is a bypass valve with a pre-set spring tension in the first place? I would have thought an oil filter bypass was in place to deal with abnormal pressures that may present within the filter, much like a cold winter start, and it opens to assure the flow of lubricant rather than have a backlog against the media.


I wouldn't consider 10~12 PSI of delta-p across the media a "high pressure event" when a filter goes into bypass. If a pretty clean oil filter is normally running at 5 PSI of delta-p, and all of a sudden increases to 10 PSI in a cold oil start-up scenario to cause the bypass valve to start opening, then the absolute pressure on the inlet side of the filter has only increased 5 PSI.

Like I said earlier, when the filter goes into bypass the flow volume of oil has not changed, only the flow path of the oil - split between the media and the bypass valve. And the pressure has increased only very slightly inside the filter on the inlet side (ie, dirty side of the media) to cause the bypass valve to open.

And again (regardless of what you're original thought was), any debris trapped in the media will stay trapped in the media in a bypass event, because there is still flow going through the media unless the media is 100% clogged. If that's the case, then things are way past the critical point of normal filter usage.

 

[Trav]

I did use the magnetic drain plugs on my motorcycles that were not OEM equipped they did catch a small amount of rubbish.
These are a shared sump of course so something like an old Mini would probably also benefit from it.

 

[dnewton3]

A magnetic filter plug is a great idea, in an engine with no filter (think lawn equipment, etc). But in a well designed and manufactured filtered engine, it's moot. It will NEVER shift the wear pattern enough to amount to anything but noise in the data.

The magnet will only attract Fe anyway; are we forgetting that other things are in play? In fact, I'd be much more concerned about soot, which will agglomerate once the OCI overwhelms the dispersant package (which is much further out in the OCI than folks think). Also, the magnet will do nothing about ingested Si; it is one of the main contributors to Fe wear. No magnet is going to alter poor air filtration. Basically, the two main causes of Fe wear are Si and Soot; a magnet will do zilch there. The Fe is a result, not a cause. You can remove some nominal portion of Fe with a magnet, but that does not stop the production of the Fe wear in the first place.

 

[ordinarybloke]

I see I've started something, in short in older generation engines a magnet of any flavour is likely to be a bigger help than in a modern engine.

And I quote:

===============================

When is the last time a bitog'r replaced an engine because it was worn out? With decent oil and filters the engine outlives the rest of the vehicle. How could adding a magnet extend the usable life of a vehicle?

===================================

With modern engines good for 200-250,000+ miles anyway, why worry. At 250,000 miles it is unlikley to be the engine that kills your car. And like it or not, a magnet, tiny or MAHOOOSIVE, put here, there or the other won't change that fact.

Conclusion: I am deluded, the only difference now is that, [sniff] thanks to you lot I know why.

Best I shuffle back under my rock.

 

[Shannow]

I keep wondering what the Cancer Council will do when they cure cancer...I sometimes think that this board is now at that point

 

[Trav]

Originally Posted By: ordinarybloke
Best I shuffle back under my rock.

Move over there are a few of us that need to crawl under there.

 

[ordinarybloke]

===========================

I keep wondering what the Cancer Council will do when they cure cancer...I sometimes think that this board is now at that point

==========================

Yes... indeed I think we might be guilty of looking-up our own "Swanny-river's" here. You know where I mean, where the don't shine. Just a tad. Sorry Gents.

 

[MushingJeep]

My 2007 GMC Sierra 2500HD came from the factory with a magnet in the end of its oil drain plug.

When the plug stripped on my 2001 GMC 2500HD I replaced it with a magnetic end one.

In neither case do I feel it is making an engine changing effect, but, it's also doing no harm and may help keep me aware of any larger issues.

Ultimately I think back to an old ad for a magnet system that you attached to your water pipes that claimed to soften your water without the salt, by suspending the nasty stuff - was ineffective. Remember, people use to drink out of clay jars that were radioactive because they thought it'd keep 'em healthy. I'm always leery of any product that isn't a basic necessity (i.e., quality engine oil) and says it will have a "vehicle changing" effect.

 

[Lapham3]

Howdy-I'm new here, but now a retired tech type fella with 45 years of putzing with the cars. I've always liked magnetic plugs in diffs-engines-trans to be able to notice some wear/problem indicators. Nice site here that I've visited some over the years-Dan Mpls. Mn.

 

[ZeeOSix]

Originally Posted By: MushingJeep

Ultimately I think back to an old ad for a magnet system that you attached to your water pipes that claimed to soften your water without the salt, by suspending the nasty stuff - was ineffective. Remember, people use to drink out of clay jars that were radioactive because they thought it'd keep 'em healthy.


Don't forget that smelling ozone in the early 1900s was a "good thing" also that people did.

 

[artificialist]

Originally Posted By: ordinarybloke
===========================

I keep wondering what the Cancer Council will do when they cure cancer...I sometimes think that this board is now at that point

==========================

Yes... indeed I think we might be guilty of looking-up our own "Swanny-river's" here. You know where I mean, where the don't shine. Just a tad. Sorry Gents.

Yeah, the USA also seems to have such a problem. Just how many awareness campaigns do we need?

In any case, I just did an oil change for a friend with a magnetic plug. The factory plug for his 2004 PT Cruiser was leaking, so I got a cheap Dorman magnetic plug as a replacement. I couldn't see anything sticking to the magnet.

It makes me wonder if the magnet is too weak to be effective, or if the 2.4L Chrysler engine produces low wear metals. I used Black Edge in that engine, I don't know what effect that had, either.

 

[ammolab]

Originally Posted By: ZeeOSix
Originally Posted By: CurtisB
Most of the wear particles I observed where likely produced from the cylinder walls which where cast iron. In modern cast aluminum engines I doubt a magnet of any placement will have a similar significance on capturing particles, as aluminum is classified as non magnetic.


Aluminum blocked engines still have iron cylinder sleeves.


Most do, but some do not. Plenty of Aluminum engines forgo the iron liner for a Nikasil coating on the Aluminum cylinder.

 

[kjbock]

Originally Posted By: ammolab
Originally Posted By: ZeeOSix
Originally Posted By: CurtisB
Most of the wear particles I observed where likely produced from the cylinder walls which where cast iron. In modern cast aluminum engines I doubt a magnet of any placement will have a similar significance on capturing particles, as aluminum is classified as non magnetic.


Aluminum blocked engines still have iron cylinder sleeves.


Most do, but some do not. Plenty of Aluminum engines forgo the iron liner for a Nikasil coating on the Aluminum cylinder.


And some engines, like my N52, use Alusil for the liner. I think some Honda engines (can't rem which ones) use cast-in carbon fiber liners.

 

[ZeeOSix]

Checkout this article on magnetic drain plugs from Blackstone Labs.

http://www.blackstone-labs.com/Newsletters/Gas-Diesel/March-1-2013.php

 

[Lapham3]

I have found the engine magnetic plugs pick up initial shavings/chip like material from the manufacturing process, and then generally just a small amount of very small 'filings'from normal wear. Differential and manual transmissions produce more as most wear items are ferous. I've only once picked up abnormal wear as the spider gears in a diff were failing. I like them and use them as an early warning as well as an indication of 'well being' during routine maint- Dan Mpls. Mn

 

[ZeeOSix]

Originally Posted By: Lapham3
I have found the engine magnetic plugs pick up initial shavings/chip like material from the manufacturing process, and then generally just a small amount of very small 'filings'from normal wear.


Yep, all I ever get on the engine's magnetic drain plug is a slight amount of what I call "black paste". Super fine ferrous metal wear, too small to be caught by a normal oil filter.